Kirstjen Nielson is the public face of a policy decried by the United Nations, the Vatican, and Democrats and Republicans alike.
One month after President Donald Trump berated her over soaring illegal immigration, US homeland security chief Kirstjen Nielsen has become the front-line defender of the administration's widely condemned practice of separating migrant children from their parents.
It's an uncomfortable position for Nielsen, who is facing opposition calls to resign as condemnation pours in from the United Nations, human rights groups, and four former first ladies - all mothers - who have called the policy "cruel" and "immoral."
With images of wailing children being wrested from their parents adding fuel to the firestorm, Nielsen took the podium Monday at the White House to defend Trump's "zero tolerance" policy of prosecuting all illegal border crossers, which is causing families to be split.
She bristled at suggestions that the children were being mistreated, or placed into what appeared to be "cages."
Instead, toeing the administration's line, she blamed Congress for passing laws that offer illegal immigrants numerous "loopholes."
And in any case the children taken from their parents after crossing the border were "well taken care of," she said.
"Our policy at DHS is to do what we're sworn to do, which is to enforce the law," she said, referring to the Department of Homeland Security.
"The image that I want of this country is an immigration system that secures our borders and upholds our humanitarian ideals."
Lawyer, cyber-security specialist
The blonde 46-year old, who swaps elegant office attire for jeans when she visits the border, kept a low profile when she joined the Trump administration in January 2017.
A lawyer by training, she had served previously as a cyber security specialist in the Department of Homeland Security.
She was brought in as assistant to Trump's first DHS secretary, John Kelly, a retired marine general who set to work cracking down on illegal immigration.
When Kelly moved to the White House as Trump's chief of staff in July 2017, Nielsen went with him as his deputy.
But by October she was back at DHS, this time as secretary.
Described as being all-business, she oversees a sprawling department with 200,000 employees and wide-ranging responsibilities.
Disaster relief, cyber security, transportation security, the Coast Guard, customs and policing the borders all fall under the department's purview.
So it has fallen to her to carry out Trump's most fiercely held objective: stopping illegal immigration.
It is a daunting, deeply controversial task in a country with an estimated 11 million people living without papers, many with families and deep roots in their communities.
But under Trump, Nielsen's department has embarked on sweeping roundups and tough new measures, including barrier construction on the Mexico border - though Congress has so far refused to fund the full 3,000-kilometre extravaganza sought by Trump.
And most recently, it has enforced a new "zero tolerance" policy towards people caught trying to cross into the United States illegally from Mexico.
Since early May, more than 2,300 children have been taken from parents arrested under the policy.
Nielsen's relationship with Trump is said to be tenuous. But despite reports he complains constantly about her performance, she has loyally defended him.
When participants in a White House session on immigration quoted Trump as referring to African nations as "shithole" countries, Nielsen came to the president's defense.
"I did not hear that word used," she told a congressional hearing.
Quizzed about Trump's statement that he would prefer immigrants from a country like Norway, Nielsen spun it as Trump's appreciation of the skills of Norwegian workers, and not their racial makeup.
"Norway is a predominantly white country, isn't it?" a senator asked her.
"I actually do not know that, sir, but I imagine that is the case," replied Nielsen - herself of Scandinavian lineage.
That has not saved her from what some call a no-win situation for anyone in her position.
After a lull for most of 2017, illegal immigration took off again at the end of the year. When statistics for April were off the map, Trump lashed out at Nielsen in a 30-minute tirade in front of the rest of his cabinet.
According to reports, Nielsen told friends she was prepared to resign.
A day later she defended her boss, saying Trump was "rightly frustrated that existing loopholes and the lack of congressional action have prevented this administration from fully securing the border."
Now, as the public face of a policy decried by the United Nations, the Vatican and politicians on both sides of the aisle, the question of her resignation is once more on the table.
But this time, it is being demanded by opposition Democrats incensed by her defense of splitting up families.
"She's allowing Trump to ruthlessly hold vulnerable children hostage, to use them as bargaining chips. This is beyond morally reprehensible," wrote the party's congressional leader Nancy Pelosi, in a post retweeted 35,000 times.
"DHS @SecNielsen must resign now."